Chain Reaction
by MagicConan14
Summary: Dazai learns that for every reaction, there is an equal and opposite reaction. Set after episode 4/chapter 5. Influenced by Dazai's novel "No Longer Human". Done for #bsdwrite number 4 (hello). Mentions of death, suicide and alcohol.


 **Characters:** Osamu Dazai, Atsushi Nakajima, Rampo Edogawa, Akiko Yosano, Ichiyo Higuchi, Ryuunosuke Akutagawa, Chuuya Nakahara (...?)

 **Pairings:** None.

 **Summary:** Dazai learns that for every reaction, there is an equal and opposite reaction. Set after episode 4/chapter 5. Influenced by Dazai's novel _No Longer Human_. Done for #bsdwrite number 4 (hello).

 **Trigger warnings:** Mentions of death, suicide and alcohol.

 **Disclaimer:** I don't own these characters.

* * *

"I thought that in killing a dreaded adversary I might actually be bringing him happiness."  
― Osamu Dazai, No Longer Human

* * *

"Hello."

No answer from his guest, so he tried a different approach.

"I know everything about you; I could tell you your whole history if you let me." His words caused the walls to reverberate slightly, but since it was an empty room made of concrete, there was nothing to shake but the wills of those present.

The person known as Osamu Dazai, who had wordlessly been observing his currently bandage-free, scarred hands as he was being spoken to, looked the speaker straight in the eye, a challenge glinting in his own like a jewel. "Tell me how I got here."

/

Knock knock. Knock knock.

"What do you want?" Rampo muttered, irked by the moonlight poking through his always-closed eyes. Admittedly, it was somewhere close to midnight, so whoever was knocking needed a good excuse to make the detective focus.

"Rampo-san," it was an out-of-breath Atsushi, Rampo could tell from the voice alone, "...Dazai's..." the former orphan forced in a breath.

"He's probably just being Dazai somewhere. You don't need Super Reasoning for that."

Atsushi waved his hand to answer in the negative. "He's comatose."

/

Dazai's body was on life support in the treatment room, and Yosano-sensei was by his side. "I can't heal him, since it seems he _wants_ to stay in there." (How ironic that a person who wished for death was currently being resurrected.)

Rampo grumbled. "Well, if he wants to be this way, there's nothing I can do." As soon as he sat down on one of the cushioned visitor chairs, he was fast asleep, ignoring the lingering smell of dampness in the air.

/

The entity that had trapped Dazai here was surely a figment of his imagination. However, if it wanted company, then so be it. Dazai wanted death anyway; this was his closest approximation at the moment.

Whenever he looked at it, it took on the appearance of Chuuya, almost as if it were a physical manifestation of hatred against him.

Chuuya finally answered after much deliberation, "It's much better if I show you how you got here." With a click of his fingers, the floor dropped out from under them and they fell, arms flailing until they grabbed on to each other's shoulders. Chuuya's hat flew off instantly, but his grip tightened on Dazai's arms instead of reaching for it.

After what seemed to be a few hours, they slowed gradually and landed like it was an aerial acrobatics show.

/

Atsushi, meanwhile, had procured some smelling salts from Yosano-sensei's supplies and was waving them under Dazai's nose. Rampo had woken up again, and was holding his nose at exactly how malodorous they were. In fact, they smelt almost like rotting river plants.

/

In this part of the mindscape, the walls served as screens, and the floor was glass. If it were a real cinema, the people who went to see the movie would've thought it was real because the memories played here were reality, once, but they were played from a third person perspective, giving Dazai a strange "out of body experience" feeling.

The sun beat down on the two viewers from above as the Yokohama riverbank came into existence on the walls. Birds chirped happily as the memory version of Dazai ran into view from the left side of the river to meet Higuchi, who'd been standing there quite patiently. It was almost like a date, and Higuchi had even let her hair down, just like she had the first time they met.

"Sorry to make you wait, Higuchi-san." He produced her business card out of his sleeve with a swift movement of his hand, and took a glance. "May I call you 'Ichiyo', or would 'Higuchi-san' be fine?"

"This is not the time for that," she chastised him, not noticing that he wasn't wearing his usual bandages, and in his sleeves were pieces of rope. "I am here on Mafia business."

Dazai chuckled, and quickly got to work with tying her hands and feet up.

Instead of the usual response of "What are you doing?!", Higuchi's face reddened. "I told you, no kidding about!"

"I've been deadly serious about this ever since I laid eyes on you," Dazai crooned, handcuffing himself to her and proceeding to tie himself up. "As a sidenote, American Boy Scout guides are fascinating, especially the part where they teach you to tie secure knots for any situation."

"A-Akutagawa-sempai will surely come," Higuchi ignored his 'sidenote' and continued. The shakiness in her voice revealed how thinly veiled the threat was, but Akutagawa would never-

-a black shadow emerged from the side of a building, cutting off this thought.

"Dazai Osamu, you _fool,"_ the Rashomon user sneered. Dazai smelt faintly like alcohol, so Akutagawa couldn't help coughing in disdain. "Are you drunk? Go where drunks go - to hell."

With that, he cleaved the handcuffs apart using a tendril of Rashomon, simultaneously shoving Dazai into the river.

/

"There are signs of Dazai's vitals again!" Atsushi heaved a sigh of relief as Yosano-sensei declared this.

Meanwhile, Rampo was bustling about, analysing the signs Dazai had left behind. "He fell into the river, and got drunk before that. He got some rope and tied it to his wrists and ankles, but he'd attached it to some other person. Knowing him, it was most likely a woman. Now, who would've been willing to follow along with Dazai's plans?"

Yosano-sensei carefully procured the business card, now floppy with water and sealed in a plastic ziplock bag, but still legible. "This was there too."

"Higuchi Ichiyo. Of course," Atsushi muttered, ready to make another call to the Mafia.

/

"So, what are you really?" Dazai mused aloud to the person who looked like Chuuya. "If you were really Chuuya-san, you would've wanted your hat back as fast as possible, and since I know I'm in a domain of your control, you could've gotten it back any time during that little show."

There was only silence and an odd warmth radiating from the surroundings, as the memory 'movie' had frozen where Dazai hit the sun-warmed water.

Chuuya's mouth twisted into a grin. "I guess it was still obvious, huh? I'm you, but a future you."

... _future_? The current Dazai's face fell, not knowing what to make of this.

As if in response to this revelation, the walls started pixelating. Soon, the scene became a linoleum-floored penthouse, with an elevator door to the duo's right and an expansive view of cerulean-windowed skyscrapers and cloudy sky to their left, obscured by a white ovoid capsule that filled up half the room. 'Chuuya' sighed and shrugged. "This is my native time. In it, I'm a time traveller of the Agency who prevents the spread of the Mafia and Guild in other parallel continuities. This was my last mission...my own continuity..."

Dazai, a time traveller? He had to stop and laugh at that, no way was he willing to meddle with the space time continuum. (He didn't even know what a 'space time continuum' _was_.)

In the memory, the true appearance of 'Chuuya' appeared as the elevator doors slid open - Dazai, approximately forty years old, in a sheer black full body suit that shimmered blue where it caught the windows' light. He marched over to the open capsule, hopped in and tinkered with the control panel inside. The witnesses climbed in, one each side of the current occupant, to find space for two more, but memory Dazai didn't register them. " _May 201X, Yokohama, current dimension"_ flashed on to the display in fluorescent blue above the controls, reflecting in the transparent visor future Dazai wore. His feet, covered in black leather boots, tapped impatiently on the floor as he continued punching in commands.

"It all went wrong from there. Atsushi-kun may have been in the Agency for 20 years, but he still got the pre-entered calculations of the routes wrong, and so I ended up stuck in your head just after the drowning incident..." 'Chuuya' buried his head in his hands with this admission.

The capsule softly closed its hatch, and just as a panicked thirty-year-old Atsushi-kun wearing future clothing forced the elevator open with clawed hands, future Dazai had disappeared.

Current Dazai and 'Chuuya' did not even feel the force that the speed of light gave, they just watched as memory Dazai reached into his pocket and pressed something, giving him the appearance of Chuuya. "Oh, I never mentioned the cloaking technology - I chose the appearance simply because I knew you'd think of me as some personification of your hatred," 'Chuuya' admitted, now that his last secret was out.

"I've got to know one thing, _Chuuya-san_ ," Dazai emphasised the name for his future self's humour, "how are you keeping me here?"

"The time machine's temporarily blocked your brain function." 'Chuuya' heaved another sigh after his seconds-long fit of laughter, then he made his hat come back. "If you agree to eradicate the Mafia and the Guild for me, I'll get your brain working again so you can change your future. Alright?" 'Chuuya' held out his hand. Well, even if the current Dazai never understood time travelling, he sure didn't want to let himself down - past, present or future - so the two Dazais shook hands. With this, the world faded to white, leaving only the present Dazai and a door into a hospital room on his left.

Dazai couldn't be comatose forever. He still had a suicide he wanted to commit.


End file.
